Following the formation of the liquid-water ocean, almost all of the CO2 will be dissolved in the ocean. For a \({\rm 5-M_{\oplus }}\)  water layer, the CO\(_2\)  mass in the envelope estimated above corresponds to a concentration of \(\sim 0.01\)  mol/L of dissolved CO\(_2\) . Here we have also assumed that the ocean is well-stirred. A higher oceanic pH leads to more effective dissolution and less CO\(_2\)  in the atmosphere. As an extreme, if cations are leached from the silicate and not charge-balanced by chloride ions, then an ocean composition with a pH of 9 – 10 (“a soda lake”) will result [1]}. Using the equilibrium constant of carbonate and bicarbonate dissociation [2]}, the CO\(_2\)  partial pressure in equilibrium with this ocean would be \(5\times 10^{-5}\sim 7\times 10^{-4}\)  bar, which is consistent with the assumed lower bound.
